Everything you need to know about HDMI 2.0a

Cables aren’t sexy technology. But if there’s one cable that gets tech enthusiasts hot under the collar, its HDMI. While many TV owners may know the technology simply as that weird flat plug that makes the TV plug-and-play, HDMI is always on the move. The all-in-one digital connection has created a cornucopia of ways to make hardware ready for the expanding AV world around us, allowing for innovations like 4K UHD technology, and more. After a jump last year to HDMI 2.0, the ever-evolving protocol has already evolved again. Say hello to HDMI 2.0a.

The best news: as with previous jumps, HDMI 2.0a does not require you replace your cables, and it won’t make any of your older electronics obsolete.

The latest move is a baby step in comparison to the last jump from HDMI 1.4a/b to HDMI 2.0, and one designed to accommodate a singular new display technology called High Dynamic Range, which we’ll refer to as HDR from here on out. Designed to vastly improve the contrast between light and dark images for a more realistic picture, HDR will be a highly touted feature in this year’s new 4K UHD TVs. As such, we’ve updated our HDMI guide to give you the skinny on what’s coming this year, as well as what’s already possible with the capable cable, thanks to a host of features you probably never knew about.

Updated on 4-22-2015 by Ryan Waniata: We’ve updated this HDMI guide to include new information for HDMI 2.0a, updated the available surround sound technologies made possible by HDMI 2.0, and added information about HDMI ARC.

The basics

As we’ve written about previously, the primary reason for the switch to HDMI 2.0 was that 4K Ultra HD televisions require much more bandwidth to realize their full potential. Since 4K Ultra HD is four times the resolution of 1080p, the former HD standard, it required more throughput to handle extra data going back and forth. Lots more.

HDMI 1.4 supported 4K resolutions, yes, but only at 24 or 30 frames per second. That works fine for movies, but isn’t useful for gaming and many TV broadcasts, which require 50 or 60 fps. Also HDMI 1.4 limited 4K Ultra HD content to 8-bit color, though it is capable of 10 or 12-bit color. HDMI 2.0 fixed all of that because it could handle up to 18 gigabits per second — plenty enough to allow for 12-bit color and video up to 60 frames per second.

But the new TVs this year are hoping to blow our minds with even higher image realism, by creating whiter more intense whites, and blacker blacks — it’s like Tide for your TV, making everything more vivid, and it’s what HDR is all about. TVs from Sony, Panasonic, LG, Samsung, and Vizio will all be touting one version or another of HDR technology. And thanks to the beauty of HDMI, the firmware update will assure HDMI 2.0a gear is fully compatible with all versions that came before it.

Don’t throw away your HDMI cables

As mentioned above, HDMI 2.0a changes nothing about the size, shape, or wiring of HDMI cables. Should you wind up getting devices that are HDMI 2.0a compliant, your existing cables will work just fine. And since HDMI 2.0a is backward compatible with older HDMI versions, you’ll be able to connect your old Blu-ray player and/or AV receiver to a brand new HDMI 2.0a-equipped 4K Ultra HD TV with absolutely no problem.

HDMI 2.0a is just a download away

According to the HDMI Forum, HDMI 2.0a will arrive in firmware updates to newer gear, or come ready to go on the latest 4K UHD TVs. And while most HDR content will likely first arrive from streaming services like Netflix and Amazon, the HDMI 2.0a will eventually allow you to connect forthcoming 4K UHD Blu-ray players, allowing for HDR content to be transmitted in the highest quality in the home, with no worries about compression artifacts or Internet bandwidth constrictions. But wait, there’s more!